Endoscopic devices are typically used by surgeons for a variety of surgical and/or diagnostic procedures. In operation, a surgeon manually applies a force, for instance, directly to the device in order to impart forward motion through a patient's body. Such devices are usually operated in conjunction with other surgical and/or diagnostic instruments, e.g., micro-arms, micro-cameras and/or laser emitters, that may be needed to complete various medical procedures.
Endoscopic devices often associated and/or used in conjunction with surgical and/or diagnostic instruments, as may be needed to complete various procedures include, e.g., micro-arms, micro-cameras and/or laser emitters. Accordingly, the instruments associated with endoscopic devices are operated by the surgeon concurrently, the surgeon applying a force to the device in order to impart their forward motion through the patient's body as well.
Other conventional endoscopic devices, however, are not capable of autonomous or semi-autonomous locomotion through a patient's body cavity of a patient. These devices comprise a tubular body of variable length with two, front and rear end portions, and an anchor for providing temporary and alternate attachment of the front end portion or rear end portions to a wall of the body cavity, thereby enabling forward motion of the device.
The variable-length tubular body of the device is a bellows-shaped tube capable of being extended or contracted through air injected therein or aspirated therefrom. In one arrangement, the device is anchored to the wall of the body cavity by a clamp associated with the front and rear end portions of the device and selectively enabled by an external control unit in synch with the successive extensions and contractions of the bellows-shaped tubular body. The clamp is actuated pneumatically by bellows-shaped members.
Once the bellows-shaped tubular body has been extended, a positive pressure is created inside the body using compressed air, thereby achieving elongation in proportion to the pressure inside, while the body contracts through progressive reduction of the pressure inside the body, until some degree of vacuum is created.
Although it has the considerable flexibility needed to negotiate the narrow intestinal loops without causing pain, the device according to the above-mentioned PCT patent application has several functional drawbacks due to its relative extendibility and friction between its outer surface and the walls of the body cavity, which have a negative effect on the device's efficiency of locomotion. Because the intestinal walls adhere partially or totally to the outer surface of the bellows, the intestinal tissue may be trapped between the folds of the bellows du ring the contraction stage. Though it does no damage the mucosa, this interferes with the progress of the device through the intestines. Moreover, given the elasticity of the mesentery and intestinal tissues, any friction between the surface of the tubular bellows-shaped body and the walls of the body cavity will stretch the tissue and mesentery instead of making the device slide along the walls, thus preventing any forward motion of the device relative to the intestinal walls during the extension stage, then allowing the tissues of the tubular cavity and the mesentery to return to their original position (with a so-called “accordion effect”) during the contraction stage.
It should be noted, moreover, that the considerable thickness of the bellows-shaped tubular body (in terms of the difference between the maximum radius and the minimum radius of the contracted and extended bellows) results in a significant reduction in the space actually available inside it, making difficult the passage of the compressed air tubes needed for the displacement of the device and making it necessary to use smaller-diameter tubes, with a consequent increase in the pressure drop and reduction in the device's speed of locomotion.